Wall plates for electrical outlets or switches are traditionally fastened by small metal screws. When these wall plates are made of variously colored polymeric material, the heads of the metal screws preferably should be colored by painting or plating to provide an identical color match. However, the color matching is not always satisfactory, and in addition considerable time and costs are involved in material handling and inventory control for maintaining suitable colored metal screws for the variously colored wall plates.
Forming the wall plate screws of polymeric material of a similar color would partially solve the material handling and inventory problems. However, known polymeric screws have threads cut therein, resulting in a weakening of the screw shank structure and easy breakage of the screw under the torque required for attaching a wall plate against an underlying surface. In addition, even when the screws are molded from the same polymeric material as is used for the wall plates, it is substantially impossible to achieve a good consistent color match with the plates because even minor variations in such production parameters as temperature cause very noticeable changes in hue and shade. Examples of prior art polymeric screws having cut threads are disclosed in U.S. Pat. Nos. 2,510,693 to Green and 3,345,899 to Fiddler.